Field of the Invention
This invention relates generally to medical instruments and laryngoscopes used to intubate patients, and more particularly to a fiberoptic intubating apparatus having a removable handle and blade which removably carries an endotracheal tube and a flexible fiberoptic bronchoscope having its fiberoptic bundle inside the endotracheal tube.
Brief Description of the Prior Art
Endotracheal intubation is a medical procedure which concerns placement of a tube in the trachea of a patient to facilitate breathing or to permit the controlled introduction of gasses through the tube by an anesthesiologist or other medical personnel. Endotracheal intubation is normally carried out after induction of anesthesia or in emergencies, and is usually accomplished without great difficulty under direct vision with a laryngoscope by the anesthesiologist. The laryngoscope is an instrument used to examine the larynx (the uppermost end of the trachea narrowed by two surrounding vocal cords and located below the root of the tongue).
With direct laryngoscopy, the patient's neck is flexed, the head is extended and the mouth is opened wide. A laryngoscope having a rigid straight blade (commonly known as a Miller-type blade), or a rigid curved blade (commonly known as a Macintosh-type blade) is placed along the right side of the tongue, and the tongue and soft tissues of the mouth are retracted anteriorly and inferiorly to enable the larynx to be seen directly through the mouth in a straight line, instead of the normal anatomic curve around the tongue from the mouth to the larynx. The endotracheal tube is then placed directly into the trachea, along this direct line of vision.
Occasionally, however, the anesthesiologist is unable to visualize the larynx using the traditional direct laryngoscopy method in a patient who has no history or signs by physical examination of being a difficult intubation. For example, many patients have decreased mobility of the head and neck, protruding upper teeth, limited mouth opening, abnormally large or small mandibles, large tongues, tumors in the oropharynx or larynx, or trauma to the face and neck, all of which prevent direct visualization for intubation of the larynx and trachea. These types of patients are usually intubated while awake and through the nose blindly or via fiberoptic endoscopy so a wide open protected airway can be maintained by the patient until it is secured by the anesthesiologist. The fiberoptic endoscope is a tubular instrument which utilizes flexible fiberoptic bundles to transmit light and visual images during examination and intubation.
Bronchoscopes are sometimes used during endotracheal intubation. A bronchoscope is a tubular instrument usually with an optical system which is designed to pass through the trachea to allow visual inspection of the tracheobronchial tree. The bronchoscope is also sometimes designed to permit passage of an instrument than can be used to obtain tissue or remove a foreign body. A fiberoptic bronchoscope is a bronchoscope which utilizes flexible fiberoptic bundles to transmit light and visual images during examination. It also contains one longitudinal channel extending from the rearward end to the tip which can be used for suctioning or insufflation of oxygen, and a lever at the proximal end to maneuver the tip up and down during use.
There are several patents which disclose various instruments used for laryngoscopy and endotracheal intubation.
Frankel, U.S. Pat. No. 4,793,327 discloses a blind intubation device which consists of an airway opening device which is inserted into the patient's mouth and adjusted to a fixed position to hold the mouth open while an automatic intubation guide is inserted for guiding an endotracheal tube into the trachea. The airway opening device has an opening through which the guide is fed into the mouth. An endotracheal tube is also fed through the airway opening device and by means of an adapter or track on the guide, the endotracheal tube is inserted into the trachea, after which the guide is withdrawn and the airway opening device is retracted from its fixed position and removed from the mouth.
Fletcher, U.S. Pat. No. 4,329,983 discloses a guide device for endotracheal tubes which includes a flexible bar that is inserted into the endotracheal tube and has a flexible line which extends along the bar and is manipulated to flex the bar in bowed fashion against the endotracheal tube to urge the tube forwardly toward the trachea and away from the esophagus. It can be used along with direct laryngoscopy in difficult patients to help facilitate passage of the endotracheal tube through the larynx.
Phillips, U.S. Pat. No. 3,856,001 discloses a rigid laryngoscope blade having a straight portion and a curved portion with a longitudinal channel for passing an endotracheal tube. An electrical lamp is secured on one side of the blade at the forward end of the straight portion and aimed inwardly and downwardly and electrical wires extend from the lamp to the handle, which contains a power source.
Bullard, U.S. Pat. No. 4,086,919 discloses a rigid fiberoptic laryngoscope having a curved blade with a connection member at the proximal end for connection to a laryngoscope handle and an eyepiece that extends outwardly from the blade at the proximal end. Fiberoptic bundles extend along the longitudinal axis of the blade and terminate at the end of the blade. An endotracheal tube may be passed beneath the blade, alongside the fiberoptic bundle into the trachea.
Lowell, U.S. Pat. No. 4,306,547 discloses a rigid fiberoptic laryngoscope having a forwardly extending blade and a tube supporting channel. A viewing assembly and light source are each connected to fiberoptic bundles which extend longitudinally through the length of the top wall and terminate at the open end of the channel.
Wu, U.S. Pat. NO. 4,982,729 discloses a rigid fiberoptic laryngoscope having an integral handle and curved blade with fiberoptic bundles which extend longitudinally through the length of the blade and terminate at the end of the blade. A bivalve element is releasably attachable to the blade to form a passageway for threading an endotracheal tube through the distal end of the blade.
Augustine, U.S. Pat. No. 5,203,320 discloses a rigid tubular contoured fiberoptic tracheal intubation guide having a through bore for holding an endotracheal tube. Correct positioning of the device is detected by external palpation of the neck of the patient and tracheal intubation is confirmed with fiberoptic visualization.
MacAllister, U.S. Pat. No. 5,016,614 discloses an endotracheal intubation apparatus having a handle and mechanism for retaining an endotracheal tube on an elongated obturator element extending from the handle and releasing the endotracheal tube therefrom. The obturator element accommodates an endoscope therethrough to permit visualization at the end thereof.
Parker, U.S. Pat. No. 5,038,766 discloses a disposable, one-piece, contoured guide element having a channel therethrough which is releasably mounted at the end of a curved blade and handle. The device is used for blindly guiding and aiming orolaryngeal and oroesophogeal tubular members.
Blind techniques of endotracheal intubation are clearly the least advantageous, as stylets, obturators, or other guides can injure the patient, and there is no visual evidence that the endotracheal tube has correctly entered the trachea.
Direct laryngoscopy requires mouth opening and head and neck positioning that may be impossible or injurious to a patient with head or neck trauma. The larynx may never be able to be identified, or the endotracheal tube may not be able to be passed through it, even if it is identified. There is usually no means for oxygen delivery or suctioning during laryngoscopy.
Rigid fiberoptic laryngoscopy will aid in locating the larynx, but it is frequently difficult to guide the endotracheal tube into the trachea without rigid stylets or other guides, which may damage the soft tissues of the head and neck. Potential obstruction of the light source or field of view by the tube itself, secretions, blood, or soft tissues, and inability to confirm proper final tube position in the trachea are drawbacks that are still present.
Lastly, independent endoscope techniques, such as flexible fiberoptic bronchoscopy and the use of malleable fiberoptic stylets suffer from inability to effectively retract tissues away from the pathway of the instrument and the endotracheal tube over it, lack of a continuous field of view protected from blood, secretions, or soft tissues, and have the potential of stylet produced injury. It is also difficult or sometimes impossible to use these types of instruments with just one hand.
The present invention is distinguished over the prior art in general, and these patents in particular by an endotracheal intubating instrument that has an elongate curvilinear blade member releasably attachable to a handle and a central channel sized to removably receive and slidably engage an endotracheal tube therein, an elongate tubular housing removably connected at its forward end to the rearward end of the endotracheal tube which removably receives a fiberoptic scope having an eyepiece at a rearward end and a fiberoptic bundle extending forwardly within the endotracheal tube, and adjustable positioning means through which the forwardly extending fiberoptic bundle passes for adjustably positioning and maintaining the tip end of the fiberoptic bundle relative to the forward end of the endotracheal tube. The apparatus is placed in the mouth, the larynx is identified, and the endotracheal tube, housing, and fiberoptic scope are advanced as a unit into the trachea as the blade is removed. Then the fiberoptic scope and housing are withdrawn, leaving the endotracheal tube in the desired part of the trachea.